CN211132455U - Infusion device with integrated occlusion sensing - Google Patents

Abstract

The utility model relates to an infusion set with sensing is blockked up to integrated form. The infusion device comprises: a pump, the pump comprising: a chamber configured with at least one port to receive fluid from the reservoir into the chamber and through which fluid flows out of the chamber; and a pumping mechanism configured to control aspiration of an amount of fluid into the chamber during an aspiration stroke and to control dispensing of an amount of fluid from the chamber during a dispensing stroke; a pump measurement device configured to generate a pump measurement relating to at least one of a suction stroke and a dispensing stroke; and a processing device configured to analyze the pump measurements and determine when the pump measurements include a plurality of pump measurements that satisfy a predetermined metric designated as indicative of an occlusion. The infusion device of the utility model eliminates the need of changing or adding any hardware.

Description

Infusion device with integrated occlusion sensing

Technical Field

The utility model relates to a system, method and equipment for jam detection. Exemplary embodiments of the present invention relate to occlusion detection using pump operation parameters, such as pump duration (e.g., aspiration stroke or dispense stroke duration) in a rotary metering pump or reciprocating pump, or pump operation monitoring switch activation status, to preclude the addition of other pressure sensing components.

Background

Diabetes is a group of diseases characterized by high blood glucose levels due to the inability of diabetics to maintain adequate levels of insulin production when needed. Diabetes can be dangerous to affected patients if left untreated, and can lead to serious health complications and premature death. However, these complications can be minimized and the risk of complications reduced by using one or more treatment options to help control diabetes.

Treatment options for diabetic patients include specialized diets, oral medications, and/or insulin therapy. An effective method for insulin therapy and diabetes management is infusion therapy or infusion pump therapy in which an insulin pump is used. An insulin pump may provide continuous insulin infusion to a diabetic patient at varying rates to more closely match the function and behavior of the normally operating pancreas of non-diabetic individuals producing the desired insulin, and the insulin pump may help the diabetic patient maintain his/her blood glucose levels within a target range based on the individual needs of the diabetic patient. Infusion pump therapy requires an infusion cannula, usually in the form of an infusion needle or flexible tubing, which pierces the skin of a diabetic patient and through which insulin is infused. Infusion pump therapy has the advantages of continuous infusion of insulin, precise dosing, and programmable delivery schedules.

Abnormalities or dysfunctions, such as leaks, blockages or the presence of air bubbles in the fluid path, may occur in the infusion pump and are not necessarily noticed by the user. There is a need to detect malfunctions such as partial or complete blockage along a fluid path in an infusion pump to maintain precisely controlled drug delivery and to advise a user to discontinue use of a faulty infusion device. A typical solution for occlusion detection is to place a pressure sensor in the infusion pump system and report an occlusion when the pressure is above a certain threshold. However, adding a pressure sensor increases the complexity of the system (e.g., increases the complexity of the mechanical, electrical, and/or software), increases the system power consumption, and increases the cost of the infusion pump.

For medical devices in which some or all of the components are disposable for ease of use and reduced cost (e.g., wearable drug delivery pumps), it is undesirable to add other components (e.g., pressure sensors) to the medical device and increase the associated cost and complexity. Therefore, there is a need for accurate occlusion detection without adding infusion pump components and without increasing the complexity and cost of the infusion pump.

SUMMERY OF THE UTILITY MODEL

The foregoing and other problems are overcome, and additional advantages are realized, by exemplary embodiments of the present invention.

It is an aspect of the exemplary embodiments to provide an infusion device with integrated occlusion sensing, including: a pump, the pump comprising: a chamber configured with at least one port to receive fluid from a reservoir into the chamber and through which fluid flows out of the chamber; and a pumping mechanism configured to control aspiration of an amount of fluid into the chamber during an aspiration stroke and to control dispensing of an amount of fluid from the chamber during a dispensing stroke; a pump measurement device configured to generate a pump measurement value related to at least one of each aspiration stroke performed by the pump and each dispense stroke performed by the pump; and a processing device configured to: analyzing pump measurements including a pump measurement for each of a plurality of strokes in at least one of the aspiration stroke and the dispense stroke; and determining when the pump measurements include a plurality of pump measurements that satisfy a predetermined metric specified as an indication of occlusion.

According to aspects of the exemplary embodiments, the infusion pump with integrated occlusion sensing further includes an indicator, and the processing device is configured to operate the indicator as an occlusion alarm in response to determining that the plurality of pump measurements satisfies the predetermined metric.

According to aspects of the exemplary embodiment, the processing device is configured to automatically terminate operation of the pumping mechanism in response to determining that the plurality of pump measurements satisfies the predetermined metric.

According to aspects of the exemplary embodiment, the pump measurements correspond to a duration of at least one of the aspiration stroke and the dispense stroke, and the predetermined metric is a selected duration that is shorter than an average of the pump measurements when no occlusion has occurred in the pump.

According to aspects of the exemplary embodiments, the pump measuring device is an end stop switch on the pump that is configured to be activated when the pumping mechanism completes at least one of the aspiration stroke and the dispensing stroke. The end stop switch is connected to the processing means to determine the duration of each of the at least one of the aspiration and dispensing strokes.

According to aspects of the exemplary embodiment, the pump measurements correspond to a duration of the end stop switch activation state, and the predetermined metric is a selected duration of the end stop switch activation state that is longer than an average of the pump measurements when no occlusion has occurred in the pump.

According to aspects of the exemplary embodiment, the pump measurements include at least two of a duration of the end stop switch activation state, a duration of at least one of the aspiration stroke and the dispensing stroke, and a time difference of the aspiration stroke and the dispensing stroke. The predetermined measure corresponding to the stroke duration is a selected duration that is shorter than the average of the stroke durations when no occlusion occurs in the pump. The predetermined measure corresponding to the difference in dispensing stroke duration relative to aspiration stroke duration is a selected duration that is greater than the average of the stroke duration differences when no occlusion occurs in the pump. The processing device is configured to analyze the pump measurements and determine when the pump measurements include a plurality of pump measurements that satisfy a corresponding one of the predetermined metrics.

According to aspects of the exemplary embodiment, the pump measurement corresponds to a time difference of the aspiration stroke and the dispense stroke, and the predetermined metric corresponding to the difference of the dispense stroke duration relative to the aspiration stroke duration is a selected duration that is greater than an average of the stroke duration differences when no occlusion occurs in the pump. According to aspects of exemplary embodiments of the present invention, the pump measurements may further include a duration of at least one of the aspiration stroke and the dispense stroke, and the predetermined metric corresponding to the stroke duration is a selected duration that is shorter than an average of the stroke durations when no occlusion occurs in the pump. The processing device is configured to analyze the pump measurements and determine when the pump measurements include a plurality of pump measurements that satisfy a corresponding one of the predetermined metrics.

It is an aspect of the exemplary embodiments to provide an occlusion sensing method for occlusion sensing in an infusion pump, comprising: operating a pump comprising a chamber configured with at least one port to receive fluid from a reservoir into the chamber and through which fluid flows out of the chamber; and a pumping mechanism configured to control the aspiration of an amount of fluid into the chamber during an aspiration stroke and to control the dispensation of an amount of fluid from the chamber during a dispensation stroke; operating a pump measurement device to produce a pump measurement value related to at least one of each aspiration stroke performed by the pump and each dispense stroke performed by the pump; and analyzing the pump measurements (which include a pump measurement for each of a plurality of strokes of at least one of the aspiration stroke and the dispense stroke) to determine when the pump measurements include a plurality of pump measurements that satisfy a predetermined metric designated as an occlusion indication.

According to aspects of the exemplary embodiments, the occlusion sensing method further includes activating an indicator to issue an occlusion alarm in response to determining that the plurality of pump measurements satisfies the predetermined metric.

According to aspects of the exemplary embodiments, the occlusion sensing method further includes automatically terminating operation of the pumping mechanism in response to determining that the plurality of pump measurements satisfies the predetermined metric.

According to aspects of the exemplary embodiments, the occlusion sensing method further includes operating the pump measurement device to generate a pump measurement corresponding to a duration of at least one of the aspiration stroke and the dispense stroke. For example, the occlusion sensing method may use the predetermined metric as a selected duration that is shorter than an average of pump measurements when no occlusion has occurred in the pump.

According to aspects of the exemplary embodiments, the occlusion sensing method further comprises configuring the pump measuring device as an end stop switch on the pump that is activated when the pumping mechanism completes at least one of the aspiration stroke and the dispense stroke; and connecting the end stop switch to a processing device configured to analyze signals from the end stop switch to determine a duration of each stroke of at least one of the aspiration stroke and the dispense stroke.

According to aspects of the exemplary embodiment, the pump measurements correspond to a duration of the end stop switch activation state, and the predetermined metric is a selected duration of the end stop switch activation state that is greater than an average of the pump measurements when no occlusion has occurred in the pump.

According to aspects of the exemplary embodiment, the pump measurements include at least two of a duration to the end stop switch activation state, a duration of at least one of the aspiration stroke and the dispensing stroke, and a time difference of the aspiration stroke and the dispensing stroke. The predetermined measure corresponding to the stroke duration is a selected duration that is shorter than the average of the stroke durations when no occlusion occurs in the pump, and the predetermined measure corresponding to the difference in dispensing stroke duration relative to aspiration stroke duration is a selected duration that is greater than the average of the stroke duration differences when no occlusion occurs in the pump. Analyzing the pump measurements includes determining when the pump measurements include a plurality of pump measurements that satisfy a corresponding one of the predetermined metrics.

According to aspects of the exemplary embodiment, the pump measurement corresponds to a time difference between the aspiration stroke and the dispensing stroke, and the predetermined metric corresponding to the difference in the dispensing stroke duration relative to the aspiration stroke duration is a selected duration that is greater than an average of the stroke duration differences when no occlusion occurs in the pump. The pump measurements may further include a duration of at least one of the aspiration stroke and the dispense stroke, and the predetermined metric corresponding to the stroke duration is a selected duration that is shorter than an average of the stroke durations when no occlusion is in the pump. Analyzing the pump measurements includes determining when the pump measurements include a plurality of pump measurements that satisfy a corresponding one of the predetermined metrics.

Additional and/or other aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The present invention can include apparatuses and methods for operating a computer system having one or more of the above aspects, and/or one or more of its features, and combinations thereof. The invention may comprise one or more of the features recited in, for example, the appended claims and/or combinations of the above aspects.

Drawings

The foregoing and/or other aspects and advantages of embodiments of the present invention will become more readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

fig. 1 and 2 are partial perspective views of an exemplary pump assembly in an exemplary drug delivery device operating according to an occlusion detection algorithm according to an exemplary embodiment;

fig. 3A and 3B are perspective views of the pump assembly of fig. 1 and 2, respectively, in an exemplary drug delivery device, arranged in accordance with a ready-to-dispense and ready-to-aspirate phase of operation;

fig. 3C is a perspective view of components in the exemplary drug delivery device, including the exemplary pump components of fig. 1 and 2 and associated circuitry on a printed circuit board;

FIG. 4 is a block diagram of components in an exemplary drug delivery device;

FIGS. 5A and 5B are diagrams illustrating pump durations of multiple aspiration operations and multiple dispense operations, respectively, of an exemplary drug delivery device under normal operating conditions;

FIGS. 6A and 6B are diagrams showing pump durations for multiple aspiration operations and multiple dispense operations, respectively, for producing the same type of drug delivery device of FIGS. 5A and 5B, but under an occlusion operating condition;

FIG. 7 is a flowchart of exemplary operation of an exemplary drug delivery device operating in accordance with an occlusion detection algorithm employing a stroke duration criterion, according to an exemplary embodiment;

FIGS. 8A and 8B depict exemplary end stop or limit switch activation data during normal and occlusion operation of an exemplary pump, respectively;

fig. 9 is a flowchart of exemplary operation of an exemplary drug delivery device operating according to an occlusion detection algorithm employing an end stop or limit switch activation duration criterion, according to an exemplary embodiment;

FIG. 10 depicts exemplary pump measurement data indicating a short dispensing stroke duration (e.g., when the pump piston cannot move during an occlusion);

FIG. 11 depicts example pump measurement data indicating extended end stop or limit switch activation duration (e.g., when pumping back to the pump reservoir due to an occlusion);

12A, 12B, 12C, and 12D depict pump measurement data from respective pumps indicating long dispensing stroke durations relative to aspiration stroke durations (e.g., when a leak occurs due to an occlusion);

FIG. 13 is a flowchart of exemplary operation of an exemplary drug delivery device operating pursuant to occlusion detection employing leak detection criteria, according to an exemplary embodiment; and

fig. 14 is a flowchart of exemplary operations of an exemplary drug delivery device operating in accordance with an occlusion detection algorithm employing a combination of criteria, according to an exemplary embodiment.

Throughout the drawings, the same reference numerals will be understood to refer to the same elements, features and structures.

Detailed Description

Reference will now be made in detail to the exemplary embodiments of the invention, which are illustrated in the accompanying drawings. The exemplary embodiments described herein illustrate but do not limit the invention by referring to the figures.

The exemplary embodiments may be used with any type of infusion pump that operates on the principle of filling a chamber (e.g., with liquid medication from a reservoir) in one stage and then emptying fluid from the chamber (e.g., to a delivery device such as a cannula deployed within a patient) in another stage. For example, a reciprocating plunger pump or a rotary metering pump may be used. In either case, the piston or plunger is retracted from the chamber to draw or suck the drug into the chamber and allow the chamber to fill with a quantity of drug (e.g., from a reservoir or cartridge of drug into the inlet). The piston or plunger is then reinserted into the chamber to dispense or expel an amount of the drug from the chamber (e.g., through the outlet) into a fluid path extending between the pump and a cannula in the patient.

For purposes of illustration, reference is made to the exemplary rotary metering pump described in commonly owned WO2015/157174, the contents of which are incorporated herein by reference in their entirety. Referring to fig. 1, 2, 3A, 3B, and 3C, an exemplary infusion pump (e.g., a wearable drug delivery device, such as an insulin patch pump) includes a pump assembly 20 connectable to a DC motor and gearbox assembly (not shown) to rotate a sleeve 24 in a pump manifold 22. A helical groove 26 is provided on the sleeve. When the sleeve 24 is rotated in one direction and then in the opposite direction, the coupling pin 28 connected to the piston 30 translates along the helical groove to guide the retraction and insertion, respectively, of the piston 30 within the sleeve 24. The sleeve has an end plug 34. After the suction stroke and thus ready for dispensing, when the piston 30 is retracted, the two seals 32, 36 on the respective ends of the piston and end plug inside the sleeve 24 define a cavity or chamber 38, as shown in fig. 3A. Thus, the volume of the chamber 38 varies depending on the degree of retraction of the piston 30. After a dispensing stroke as shown in fig. 3B and thus ready for aspiration, when the piston 30 is fully inserted and the seals 32, 36 are substantially in contact with each other, the volume of the chamber 38 is negligible or substantially zero. Two ports 44, 46 are provided relative to the pump manifold 22, the pump manifold 22 including: an inlet 44 through which drug may flow from a reservoir 70 (FIG. 4) for the pump 64 (FIG. 4); and an outlet 46 through which medicament that has been drawn into the chamber 38 (e.g. by retraction of the piston 30 during a phase of the pumping operation) may be dispensed from the chamber 38 into a fluid path, e.g. to a cannula 72 (fig. 4) within the patient, by reinserting the piston 30 into the chamber 38.

With continued reference to fig. 1, 2, 3A, 3B, and 3C, the sleeve 24 may be provided with an aperture (not shown) that is aligned with either the outlet 46 or the inlet 44 (i.e., depending on the degree of rotation of the sleeve 24 and thus the degree of translation of the piston 30) to allow the medicament in the chamber 38 to flow through the corresponding one of the ports 44, 46. A pump measuring device 78 (fig. 4), such as a sleeve rotation limit switch, may be provided having, for example, an interlock 42 on the sleeve 24 or end plug 34 thereof and one or more detents 40 that cooperate with the interlock 42. An interlock piece 42 may be mounted at each end of the manifold 22. When the pump 64 is in the first position, the detent 40 at the end face of the sleeve 24 is adjacent the ridge 48 of the interlock piece 42, whereby the side hole in the sleeve 24 is aligned with the inlet 44 to receive fluid from the reservoir 70 into the chamber 38. Under some conditions (e.g., back pressure), it may be that the friction between the piston 30 and the sleeve 24 is sufficient to cause the sleeve 24 to rotate before the piston 30 and the coupling pin 28 reach either end of the helical groove 26. This can result in an incomplete amount of liquid being pumped per stroke. To prevent this from occurring, the interlock 42 prevents the sleeve 24 from rotating until the torque exceeds a predetermined threshold, as shown in FIG. 3A. This ensures that the piston 30 is fully rotated within the sleeve until the coupling pin reaches the end of the helical groove 26. Once the coupling pin 28 strikes the end of the helical groove 26, further movement of the DC motor and gearbox assembly or other type of pump and valve actuator 66 (fig. 4) increases the torque acting on the sleeve 24 beyond a threshold, thereby flexing the interlock 42 and allowing the brake 40 to pass over the bump 48. With sleeve 24 rotated to complete its side hole orientation with cannula 72 or outlet 46, detent 40 moves past bump 48 in interlock 42, as shown in fig. 3B. Another sleeve feature 41 may be provided to engage an electrical switch (e.g., an end stop switch 90 disposed on a printed circuit board 92 and arranged relative to the sleeve and/or end plug 34 to mate with the pump measuring device 78, as shown in fig. 3C).

Fig. 4 is an exemplary system diagram illustrating exemplary components in an exemplary drug delivery device 10 having an infusion pump (e.g., the pumps of fig. 1, 2, 3A, 3B, and 3C). The drug delivery device 10 may comprise: an electronics subsystem 52 for controlling the operation of components in the fluidic subsystem 54, such as pump 64; and an insertion mechanism 74 for deploying the cannula 72 for insertion into an infusion site on the skin of a patient. The power storage subsystem 50 may include a battery 56, for example, for providing power to components in the electronics subsystem 52 and the current control subsystem 54. The fluidics subsystem 54 may include, for example, an optional fill port 68 in order to fill the reservoir 70 (e.g., fill the reservoir 70 with a drug), although the drug delivery device 10 may optionally be shipped from a manufacturer having already filled its reservoir. The flow control subsystem 54 also has a metering subsystem 62 that includes a pump 64 and a pump actuator 66. As described above, the pump 64 may have two ports 44, 46 and associated valve subassemblies that control when fluid enters and exits the pump chamber 38 via the respective ports 44, 46. One of the ports is inlet 44, through which inlet 44 fluid, such as liquid medicament, flows from reservoir 70 into pump 64 due to, for example, an aspiration or pull stroke of the pump acting on pump plunger or piston 30. The other port is the outlet 46 through which fluid exits the pump chamber 38 and flows to the cannula 72 for delivery to the patient pump as a result of a pump discharge or push stroke acting on the pump plunger or piston 30. The pump actuator 66 may be a DC motor and gear box assembly or other pump drive mechanism for controlling the plunger or piston 30 and other associated pump components, such as the sleeve 24, which may be rotated relative to the translational movement of the pump piston 30. The microcontroller 58 may be provided with an integrated or separate memory device having computer software instructions to activate, for example, rotation of the sleeve 24 in a selected direction, translation or axial movement of the piston 30 in the sleeve 24 for a suction or dispensing stroke, and optionally rotation of the sleeve 24 and piston 30 together during a change in valve state as described in WO2015/157174 above. As described below, an occlusion detection algorithm according to an exemplary embodiment may be provided to microcontroller 58 to monitor pump measurements and detect when an occlusion operating condition associated with an infusion pump occurs.

Regardless of the type of pumping mechanism 64 used to draw a controlled volume of medicament into the pump chamber 38 and dispense the controlled volume of medicament from the pump chamber, the pump 64 has associated therewith an expected pump duration for one or both of the drawing and dispensing phases or strokes attributable to the pump characteristics. For example, in the exemplary pump assembly 20 shown in fig. 1, 2, 3A, 3B and 3C, the pump duration for drawing drug into the chamber and dispensing drug from the chamber 38 is affected by pump characteristics such as the internal volume of the pump chamber 38, the length or distance of the pump piston stroke, the characteristics of the port seals provided at the inlet and outlet ports 44, 46, and the like. When the pump pressure is within a specified relative normal operating range, the pump duration for filling the chamber 38 with a specified volume (e.g., a desired dose) of fluid and for expelling the specified volume of fluid from the chamber may be determined and used as a baseline for monitoring normal operating conditions of the pump 64 and for determining when an abnormal operating condition occurs, such as due to leakage of fluid from the pump chamber or a blockage in the pump fluid path, whereby in either case, the specified volume of fluid (e.g., the desired dose) cannot be delivered from the chamber via the dispensing stroke. This may be undesirable because the patient will not receive the required dose.

As mentioned above, a typical solution for occlusion detection is to place an additional pressure sensor in the pump control system and report an occlusion when the pressure is above a certain threshold. However, adding a pressure sensor has the disadvantage of increasing the complexity of the system (e.g., mechanical, electrical, and/or software complexity), increasing the system power consumption, and/or increasing the cost of the pump. These disadvantages are particularly disadvantageous for wearable pump designs, where all or part of the pump will be disposable once the reservoir 70 is emptied or the pump 64 has been used for a selected amount of time and/or to deliver a selected amount of medication.

According to an exemplary embodiment, occlusion detection is accomplished without additional components such as occlusion sensors disposed upstream or downstream of pump 64. When the microcontroller 58 or other processing device used to control pump operation has performed pump duration measurements for normal operation (e.g., for one or both of an aspiration stroke and a dispense stroke), the microcontroller 58 can be further controlled to determine when the pump duration measurements are outside of a specified range of normal operating conditions and thus indicate an occlusion, and to generate an indication that an occlusion is detected. Thus, the pump 64 and/or the entire drug delivery device 10 may in turn be replaced or repaired, thereby ensuring that the patient is receiving the full intended dose provided under normal operating conditions.

When performing pump duration measurements for pump operation, occlusion detection may be accomplished by adding computer software instructions to microcontroller 58 or a remote device controlling drug delivery device 10, such as operation that monitors pump duration and determines when a specified pump duration threshold or other criteria for normal pump operating conditions are not met. Therefore, occlusion detection is achieved by a software solution and no hardware changes to the pump are required. As described below, there is a significant difference in pump duration between a normal pump and a blocked pump; therefore, the false alarm rate and the false failure rate are very low. Thus, an occlusion detection algorithm constructed according to aspects of the exemplary embodiments is able to provide reliable occlusion detection results.

For example, determining a pump duration threshold or range of values or other metric indicative of an occlusion may be performed empirically for a selected type of pump 64. The metric of a selected type of pump experiencing normal operating pressure may be compared to the metric of the same type of pump but experiencing at least partial or complete occlusion. For example, an occlusion in the downstream path from an occluded pump 64 to its cannula 72 causes the pressure in the fluid path of the pump 64 to increase over time. The clogged pump eventually begins to leak when the pressure in the clogged pump exceeds a threshold. A log file of normal and clogged pumps may be generated to obtain a corresponding history of pump duration information for an aspiration stroke and/or a dispense stroke. However, it should be understood that different pump measurements other than pump duration (i.e., duration of aspiration or dispense strokes) may be used to determine differences in pump operation during normal and occlusion operating conditions and to determine thresholds for monitoring pump operation and distinguishing normal operating conditions from occlusion operating conditions. For example, as described below, an extended end-of-stroke switch may be used to activate or differentiate between significant differences in the respective durations of the aspiration and dispensing strokes to detect the occurrence of an occlusion.

Referring to fig. 5A and 5B, the pump duration (e.g., on average about 1.5 seconds) of a pump experiencing a blockage is significantly shorter than the pump duration (e.g., on the order of 3 to 3.5 seconds) of a pump 64 operating under normal conditions, a phenomenon of shorter pumping duration being associated with the pumping mechanism, such as the silicon seals on the piston 30, sleeve 24, interlock 42, and inlet and outlet ports 44, 46 described above in connection with fig. 1, 2, 3A, 3B, and 3C. As described above, different types of pumps 64 may be improved by implementing occlusion sensing according to example embodiments, and different pump components may contribute to a shortened pump during an occlusion condition. The pump 64 may be a rotary metering type pump or a reciprocating pump or other type of pump that employs aspiration or aspiration of fluid from an upstream reservoir and then discharge or dispense of the fluid to a separate downstream fluid path leading to the patient.

With reference to the exemplary infusion pump 64 described above in connection with fig. 1, 2, 3A, 3B, and 3C, the pump suction stroke and the dispensing stroke driven by the piston 30 translating within the outer plastic sleeve 24 are related to the switching of the pump 64 between the upstream fluid path and the downstream fluid path. As the piston 30 rotates (e.g., by a DC motor and gearbox assembly, not shown), the piston 30 translates through the sleeve 24, which is guided by the travel of the pin 28 on the piston through the helical groove 26 in the sleeve 24. Once the piston 30 has translated completely through the sleeve 24 and completed its fluid aspirating or dispensing phase, it engages the sleeve 24 directly via the pin 28 in the slot 26 and the rotation of the piston 30 and sleeve 24 become coupled. This allows the sleeve 24 to rotate between the upstream and downstream fluid paths and activate an end-of-stroke electrical switch 90 or other component associated with the pump measurement device 78 (fig. 4) and disposed on the pump 64 and/or in the drug delivery device 10. During normal operation, the presence of the interlock 42 prevents the piston 30 and the sleeve 24 from rotating before the piston 30 completes its action of translating through the sleeve 24. However, if the pressure in the downstream fluid path increases beyond a threshold, the rotation of the piston 30 and sleeve 24 couple and allow the sleeve 24 to pass under the interlock 42 and activate the switch 90 (e.g., activate the switch via the sleeve feature 41 associated with the pump measurement device 78) before the piston 30 completes its action of translating through the sleeve. This significantly shortens the pumping duration (e.g., from 3 to 3.5 seconds during normal conditions to less than 2 seconds during occlusion conditions).

Referring now to fig. 6A and 6B, pump duration data from a plurality of similar types of pumps 64 over a plurality of pump cycles is shown. For example, log data from 19 pumps completing 600 cycles is shown, with 10 pumps running under normal conditions and 9 pumps running under occlusion conditions. As can be seen in fig. 6A and 6B, all clogged pumps have a pump duration segment of less than 2 seconds. Some pump durations return to normal, which may be due to pressure relief due to leakage at the manifold area. The clear difference in pump duration between a normally operating pump and a pump experiencing an occlusion allows for the use of an occlusion detection algorithm based on pump duration.

Referring to fig. 7, an exemplary occlusion detection process includes setting a pump measurement threshold or metric, such as a stroke duration threshold (block 80), where a stroke duration above the threshold indicates normal pump operation and a stroke duration below the threshold indicates occlusion. To set the threshold, the pump measurement data is analyzed. For example, the aspiration stroke duration and the dispense stroke duration may be detected by a limit switch or other pump measuring device 78 (fig. 4) provided to the pump. In the exemplary pumps described with reference to fig. 1, 2, 3A, 3B, and 3C, a sleeve rotation limit switch or other pump measuring device 78 is used to determine the stroke or pump duration. For example, the microcontroller 58 and other electronic components such as the end stop switch 90 that cooperate with the sleeve feature 41 may generally be disposed on a Printed Circuit Board (PCB)92 associated with the pump 64 or the delivery device 10. The end stop switch activation data may be collected and stored (e.g., by a memory device integrated with microcontroller 58 or as a separate component on PCB 92). The microcontroller 58 may be provided with a jam detection algorithm for processing the end stop switch activation data to determine if a jam has occurred. According to another exemplary embodiment, the end stop switch activation data may be provided (e.g., wirelessly or by a wired connection) from the pump 64 to another apparatus having an occlusion detection algorithm (e.g., a handheld remote control for the pump 64) or a non-dedicated computing device (e.g., a mobile phone, Personal Computer (PC), laptop, or other portable computing device) provided with software or app that includes the occlusion detection algorithm.

Pump measurement data is obtained for one or more of the same type of pumps operating under normal conditions, and pump measurement data is obtained for one or more of the same type of pumps operating under occlusion conditions, as shown in fig. 5A and 5B and fig. 6A and 6B. The pump measurement data for the two sets of pumps may be averaged or otherwise aggregated or sorted and then analyzed to determine the degree of difference between the pump measurements for a normally operating pump and the pump measurements for an occluded pump. The threshold or other metric is determined as a value or range of values with margins above and/or below which normal pump measurements will not fall. The values, or ranges of values, and/or margins may be specified by a user or automatically determined based on pump measurement data obtained from the pump. As noted above, pump measurement data is data that is generated and monitored during normal pump activity and therefore is not an additional component that adds operation or requires increased pump complexity.

With continued reference to fig. 7, once the pump measurement metric (e.g., stroke duration threshold) is set, the microcontroller 58 in the drug delivery device 10 is controlled by the occlusion detection algorithm to obtainPump measurement data (e.g., stroke duration data) for the pump is obtained (block 81), and the stroke duration data for each pump operating phase or operating cycle period (e.g., for each pump cycle) is compared to the pump measurement metric (block 82). When the stroke duration data satisfies the pump measurement metric (e.g., greater than or equal to 2 seconds Th of the pump 64_stroke) It is determined that the pump is operating properly (block 84). When the stroke duration data does not satisfy the pump measurement metric (e.g., is below an occlusion detection threshold (e.g., less than 2 seconds Th of pump 64)_stroke) Time) then it is determined that the pump is experiencing an occlusion condition. When the threshold Th for normal operation is not satisfied_strokeThe counter is incremented (block 83). Referring to block 85, when the counter reaches a selected value (e.g., corresponding to threshold Th where normal operation is not met_strokeCounter value of 8 pump cycles of 8), an occlusion is detected. A total number of cycles to reach a selected number of cycles before an occlusion is indicated may be specified, such as 8 consecutive cycles of 8 cycles or within a specified number of cycles (e.g., 20 cycles). The microcontroller 58 may be configured by the occlusion detection algorithm to generate a selectable indication of the detection of an occlusion error (block 86) and automatically stop operation of the pump and/or the drug delivery device 10 and/or generate a selectable indication to the user to stop use of the pump (block 88). If the counter has not reached the selected counter value after incrementing per block 83, then collection of pump measurement data continues per block 81. Since the occlusion detection algorithm is based on pump duration data or other pump measurement data that has been implemented in the pump, occlusion detection is accomplished by checking the pump duration or other measurement data in the software against a selected threshold or metric. Thus, a software-based solution is provided to detect congestion, so that no hardware changes are required.

The example pump 64 described in connection with fig. 1, 2, 3A, 3B, and 3C uses one or more on/off limit switches to determine the system state at the rotational travel limits. For example, a multi-stage pump (i.e., a pump that draws fluid to fill a chamber in one stage and then discharges the pump chamber in the next stage) may use some type of end stop switch for each stage to detect when a piston and/or sleeve or other pump component reaches a predetermined position corresponding to a position at which aspiration or dispensing is complete. However, it should be understood that a different mechanism or other pump measuring device 78 may be used to determine the pump measurement (e.g., pump duration) in addition to the interlock 42 and the sleeve rotation limit switch (e.g., end stop switch) 90. Alternatively, the pump 64 may employ one or more optical sensors or encoders with optical switches to determine the position of the pump components at their end stop positions for complete aspiration and/or dispensing.

Thus, as described with reference to fig. 7 and in accordance with an exemplary embodiment of the present invention, the time required to fill the chamber and the time required to expel the required amount of fluid from the chamber are determined, at least the discharge time per stroke is measured, and an indication is generated indicating that a blockage is detected when a selected number of discharge times do not exceed a specified amount (e.g., the stroke duration is shortened over a specified number of pump cycles).

According to another exemplary embodiment, occlusion detection is performed by monitoring the duration of activation or triggering of a pump end stop or limit switch, as described below with reference to fig. 9. Monitoring short pump stroke durations as described above in connection with fig. 7 can be processed separately or in combination to process monitoring data relating to the duration of detected activation or triggering of the pump end stop or limit switch to determine if an occlusion has occurred in the pump 64.

As described above, during normal operation, the presence of the interlock 42 prevents the piston 30 and the sleeve 24 from rotating before the piston 30 completes its translation through the sleeve 24. However, as pressure builds in the downstream fluid path (i.e., during a blockage), the rotation of the piston 30 and sleeve 24 may couple prematurely; that is, the sleeve 24 rotates prematurely before the intended rotation during a valve state change (e.g., during normal pump operation when the sleeve 24 is at the end of completing a piston stroke and is rotating without axial movement to align its side port with a corresponding one of the ports 44, 46). This premature rotational coupling of the piston 30 and sleeve 24 in turn allows the sleeve 24 to pass under the interlock 42 and trigger the switch 78 before the piston 30 completes its axial translation through the sleeve. This significantly shortens the pumping duration (e.g., measured as the time period or duration between pump motor activation and end stop switch signals), as explained above in connection with fig. 7. Additionally, another pump operating characteristic that may be monitored for occlusion detection is the duration of time that the pump measuring device 78 and its associated switch 90 are in an activated or triggered operating mode or otherwise indicate the beginning of an activation state.

In some cases, the pump duration in a clogged pump system may remain normal and not decrease as expected; thus, monitoring another pump measurement parameter or characteristic may improve occlusion detection accuracy. For example, in the event that the pump sleeve 24 rotates prematurely as expected due to a blockage in the pump system, as long as the pump sleeve opens into the upstream fluid path (and before the end-of-stroke signal from the switch 90), the piston may begin to advance and distribute the fluid payload back into the upstream fluid path. Because the piston 30 and sleeve 24 can rotate throughout their angular position range, the total pump operation time remains constant with and without clogging. On the other hand, since the piston 30 is now rotated and translated through the sleeve 24 after the sleeve has been rotated on the upstream channel, the end stop switch 90 is now triggered for an extended period of time. Thus, occlusion detection may include monitoring for extended or extended end stop limit switch activation or triggering alone or in addition to monitoring for shortened pump stroke duration according to exemplary embodiments.

To further illustrate how the activation or triggering of the pump measuring device may be extended due to an occlusion, reference is made to an exemplary pump 64 described in accordance with the exemplary embodiment shown in fig. 1, 2, 3A, 3B, and 3C. During normal pump 64 operation, when the end stop switch 90 is first struck and dragged by the pump sleeve 24 (e.g., by the sleeve feature 41 engaging the end stop switch 90) and is thus triggered, the end stop switch 90 produces a drop in the end stop switch voltage signal from 1.8V to 0V, which is provided to the microcontroller 58. Only after the switch 90 is released (e.g., by disengagement of the sleeve feature 41) and the spring is back in center, does the end stop switch voltage return to 1.8V. In some cases, the side port of the sleeve 24 opens into the upstream fluid path (e.g., aligned with the inlet 44) before the piston 30 completes its axial translation and the end stop switch 90 has disengaged from the sleeve feature 41, and when the pressure in the upstream fluid path is low, the piston 30 may begin to advance and translate through the sleeve 24, thereby emptying the pump contents into the upstream fluid path while the end stop switch 90 is in the intermediate trigger state. The net result is that the activation signal (e.g., voltage drop) of the end stop switch 90 occurs over an extended period of time. This pump clogging characteristic is illustrated in fig. 8A and 8B, which illustrate a normal duration of switch 90 activation (e.g., 0 volts) of less than 0.5 seconds and extended end stop or limit switch 90 activation (e.g., 0 volts) of almost 1.5 seconds, respectively.

There are several reasons why some pumps 64 may exhibit a shorter total pump duration (e.g., when the piston 30 fails to advance), while some pumps 64 may exhibit an increase in the duration of the end stop switch 90 activation signal (e.g., when the piston 30 advances in the upstream fluid path). For example, the alignment of the switch 90 on the PCB 92 with the associated pump components (e.g., interlock 42, detent 40, and sleeve feature 41) may allow for such variability in which sleeve angular position the end stop switch 90 is released and thus when the end stop switch activation signal is generated and provided to the microcontroller 58. Additionally, high pressure in the upstream fluid path from the larger insulin reservoir fill volume may prevent the piston 30 from advancing in the upstream fluid path (e.g., resulting in a shorter pumping duration), while lower pressure in the upstream fluid path from the small insulin reservoir fill volume may allow the piston 30 to advance in the upstream fluid path (e.g., resulting in a longer or extended end stop or limit switch activation or "toggle" duration).

Referring to FIG. 9, an exemplary occlusion detection process includes setting a pump measurement threshold or metric, such as a switch activation duration threshold(block 96) where a switch activation duration below a threshold indicates normal pump operation and a switch activation duration above the threshold indicates occlusion. To set the threshold, the pump measurement data may be analyzed. For example, a plurality of identical pumps 64 may be tested with similar occlusion conditions to collect pump measurement data associated with a significant increase in pump measurement parameters that show a significant duration, such as a voltage drop in the end stop switch signal when the pump is occluded. With exemplary empirical measurements of the pump 64 in fig. 1, 2, 3A, 3B, and 3C, the switch activation duration during occlusion is approximately 1.5 seconds, which is commensurate with the expected amount of time for the piston 30 to fully translate through the sleeve 24. Thus, the occlusion detection algorithm may be configured to record the signal duration of the end stop switch 90 according to software instructions (e.g., in the microcontroller 58) and to correlate the recorded switch 90 activation duration to a threshold (e.g., Th)_switch>1.0 second) to determine if an occlusion exists, as shown in block 98 of fig. 9. For example, end stop or pump limit switch activation data may be collected and stored (e.g., by a memory device integrated with microcontroller 58 or implemented as a separate component on PCB 92). The microcontroller 58 may be provided with a jam detection algorithm for processing the end stop switch activation data to determine if a jam has occurred. According to another exemplary embodiment, the end stop switch activation data may be provided (e.g., wirelessly or by a wired connection) from the pump 64 to another apparatus having an occlusion detection algorithm (e.g., a handheld remote control for the pump 64) or a non-dedicated computing device (e.g., a mobile phone, Personal Computer (PC), laptop, or other portable computing device) provided with software or app that includes the occlusion detection algorithm. The switch activation duration data for an occluded pump may be averaged or otherwise aggregated or sorted and then analyzed to determine the degree of difference between similar pump measurements for a normally operating pump and pump measurements for an occluded pump. Threshold value (e.g., Th_switch) Or other metric, is determined as a value or range of values with margins above and/or below which the pump measurement will not be. The value, or range of values, and/or margin may be specified by a userOr automatically based on pump measurement data obtained from the pump. As described above, pump measurement data (e.g., switch activation duration) is data that is generated and monitored during normal pump activity, and therefore does not require additional components that would increase the complexity of the pump.

With continued reference to fig. 9, once the pump measurement metric (e.g., switch activation duration threshold) is set, the microcontroller 58 in the drug delivery device 10 is controlled by the occlusion detection algorithm to obtain pump measurement data (e.g., switch activation duration data) for the pump 64 (block 97), and compare the switch activation duration data to the pump measurement metric during various pump operating phases or cycles (e.g., for each pump cycle) (block 98). When the switch activation duration data satisfies the pump measurement metric (e.g., Th less than or equal to 1.0 second_switch) It is determined that the pump is operating properly (block 100). When the switch activation duration data does not satisfy the pump measurement metric (e.g., an occlusion detection threshold Th of greater than 0.1 seconds)_switch) It is determined that the pump is experiencing an occlusion condition. When the threshold Th for normal operation is not satisfied_switchThe counter is incremented (box 99). Referring to block 101, when the counter reaches a selected value (e.g., corresponding to a threshold Th where normal operation is not met_switch8 pump cycles, 8), then an occlusion is detected. A total number of cycles to reach the selected number of cycles before occlusion is indicated may be specified, such as 8 consecutive cycles of 8 cycles or within a specified number of cycles (e.g., 20 cycles). The microcontroller 58 may be configured by the occlusion detection algorithm to generate a selectable indication of the detected occlusion error (block 102) and automatically stop operation of the pump 64 and/or the drug delivery device 10, and/or generate a selectable indication to the user to stop use of the drug delivery device 10 (block 104). If the counter has not reached the selected counter value after incrementing per block 99, then collection of pump measurement data continues per block 97. Since the occlusion detection algorithm is based on pump duration data or other pump measurement data that has been implemented in the pump, occlusion detection is accomplished by checking the pump duration or other measurement data in the software against a selected threshold or metric. Thus, a software-only based solution is provided to checkThe blockage is measured so that no hardware changes are required.

According to another exemplary embodiment of the present invention, a third pump characteristic is monitored to detect an occlusion in the drug delivery device 10, as described below in connection with fig. 13. For example, testing a selected pump 64 in an occluded state shows that if occlusion occurs when the drug delivery device 10 is new, the pump 64 tends to have a short stroke duration or a long end stop duration, as described above in connection with fig. 7 and 9, respectively. However, after the pump has gone through many cycles, the test data shows that it is prone to leakage at the junction area 49 between the manifold seal 47 and the sleeve 24, as shown in fig. 3B. The cause of excessive leakage after certain pump cycles may be a combination of wear and tear of the seal caused by repeated pumping motions and high internal pressure caused by clogging. In other words, when pump 64 is new and seal 47 is strong enough to tolerate the high pressures introduced by a blockage, the pump may exhibit a short stroke duration or a long end stop duration (e.g., extended limit switch activation duration) during the blockage. However, after some pump cycles, the seal is not sufficient to withstand the high pressures introduced by the blockage, and the pump 64 may leak through the weakest link of the downstream fluid path, which may be the seal 49 between the manifold 47 and the sleeve 24. The pump motor (not shown) needs to provide more energy to push the fluid through since the high internal pressure introduced through the blockage forces the fluid in the pump chamber 38 through the leak path. As a result, the dispensing stroke duration during occlusion is longer than in normal operation.

Fig. 12A, 12B, 12C, and 12D illustrate some examples of baseline occlusion tests from a selected type of pump (e.g., pump 64 described with reference to fig. 1, 2, 3A, 3B, and 3C). Fig. 12A, 12B, 12C and 12D show long dispensing durations associated with leaks caused by clogging. Each of the graphs in fig. 12A, 12B, 12C and 12D corresponds to one drug delivery device 10 for four drug delivery devices 10, respectively. Each drug delivery device 10 is for example filled with 300U of fluid and 50U open for delivery, 2U clamped, and 2U open. As can be seen from these figures, when the drug delivery device 10 is occluded, the dispensing stroke duration increases while the aspiration stroke duration remains substantially the same. Thus, the pump characteristic can be used to detect leaks caused by clogging.

In accordance with an aspect of exemplary embodiments of the present invention, the occlusion detection algorithm as described above may employ a pump duration difference between a dispense stroke and a suction stroke. For example, referring to block 108 in FIG. 13, the travel difference threshold (Th) may be determined as follows_delta)：

Step 1: at the end of the priming, the average duration difference between the aspiration stroke and the dispensing stroke is calculated, defined as:

where n is the number of strokes used to obtain the average difference. By way of example, n-3 is used in the exemplary embodiment, but it should be understood that this number may vary depending on the particular pump design.

Step 2: for each pump cycle after priming, pump measurement data (e.g., the duration difference between the aspiration stroke and the dispense stroke) of the pump 64 is collected (block 109) and the duration difference data is compared to a pump measurement metric (block 110), e.g., as follows:

1) calculating the duration difference: di-suction is assigned;

2) subtract D0 from Di: Di-D0; and

3) it is checked whether D ' i D ' i-1 and D ' i-2 are less than a given threshold (e.g., 0.13 seconds), as shown in block 110 of FIG. 13. If so, normal pump operation can continue as indicated by block 112 in FIG. 13. If not, a leak is detected and it may be determined that the pump is experiencing a blockage condition. When the threshold Th for normal operation is not satisfied_deltaThe counter is incremented (block 111). Referring to block 113, when the counter reaches a selected value (e.g., corresponding to where the threshold Th for normal operation is not met_deltaCounter value of 8 pump cycles of 8), occlusion is detected and an occlusion indication may be generated as per block 114, and as perThe pump operation is terminated in block 116. If the counter has not reached the selected counter value after incrementing per block 111, then collection of pump measurement data continues per block 109. A total number of cycles to reach a selected number of cycles before occlusion is indicated may be specified, such as 8 consecutive cycles of 8 cycles or within a specified number of cycles (e.g., 20 cycles). Although three consecutive dispensing strokes are used in the exemplary embodiment, the number may vary depending on the duration of the pump over time. Duration difference D_0,1,...,_xMay be averaged or otherwise summed or classified and then analyzed to determine the degree of difference between the pump measurements of a normally operating pump (e.g., aspiration stroke and dispense stroke duration difference) and the pump measurements of an occluded pump, and/or relative to a threshold or other metric Th_deltaThe degree of difference in (c).

According to other exemplary embodiments, the jam detection algorithm may include the leak detection criteria described in fig. 13 in conjunction with the stroke duration criteria described in fig. 7 and/or the end stop or limit switch activation duration criteria described in fig. 9. For example, detection using all three criteria, or only one or a subset of the three criteria, may be performed in parallel or in series using occlusion detection software provided to microcontroller 58 or a controller of a separate device associated with drug delivery device 10. Additional example data for the trip duration criteria is shown in fig. 10, and additional example data for the switch activation duration criteria is shown in fig. 11. Referring to fig. 14, an exemplary jam detection algorithm according to an exemplary embodiment employs a combination of a travel duration criterion as described in fig. 7, an end stop or limit switch activation duration criterion as described in fig. 9, and a leak detection criterion as described in fig. 13. The counter that detects the occlusion condition is cleared or set to a value of 0 (block 120). As shown in block 122, pump cycling is detected (i.e., aspiration and dispense strokes are detected using, for example, end stop switch activation data). Pump measurement data is collected (block 124), such as stroke duration, end stop duration described with reference to FIG. 9, and aspiration stroke and dispense line during primingThe average duration difference between the runs. A stroke duration difference is determined (i.e., the average duration difference during priming is subtracted from the duration corresponding to the dispensing stroke duration being less than the aspiration stroke duration (block 126) — if an abnormal pump operating condition is detected (e.g., the dispensing stroke duration of block 128 is shortened (e.g., less than 2 seconds Th)_stroke) Or the end stop switch activation duration of block 132 is extended (e.g., Th greater than 1 second_switch) Or the difference in the duration of the trip of block 134 (e.g., Th with a difference greater than 0.13 microseconds)_delta) Then the counter is incremented (block 136). When the counter reaches a selected value in block 138 (e.g., counter value 8 corresponding to 8 pump cycles where the threshold for normal operation is not met), block 140 detects an occlusion and, for example, an occlusion indication may be generated and/or pump operation may be terminated. If these occlusion conditions are not met, the counter remains clear (e.g., a 0 value) at block 134 and the next pump cycle is detected and the associated pump timing or measurement data is collected as per block 122.

For example, the leak detection criteria described above in connection with the occlusion detection algorithm of fig. 13 are applied to the baseline occlusion data collected from the 280 drug delivery devices 10 in connection with the short stroke duration algorithm (e.g., described above in connection with blocks 80 and 82 in fig. 7) and the long end stop duration algorithm (e.g., described above in connection with blocks 96 and 98 in fig. 9). Table 1 shows a comparison between two cases where the leak detection algorithm described with reference to blocks 108 and 110 in fig. 13 is not utilized and utilized. It can be seen that the leak detection algorithm (e.g., blocks 108 and 110 in fig. 13) significantly improves the correct jam detection rate of the jam detection algorithm according to exemplary embodiments of the present invention. However, it may slightly increase the false alarm rate.

Table 1: occlusion detection w/and w/o leak detection

Of the 280 drug delivery devices 10, 120 drug delivery devices 10 deliver a 10U bolus prior to clamping. The manifold seal 49 in these drug delivery devices 10 is used minimally. Table 2 shows a comparison between not using and using the leak detection algorithm for the set of drug delivery devices 10. As can be seen from table 2, if the manifold seal 49 is used minimally, the occlusion detection rate is very high, 88%, even if no leak detection algorithm is added to the occlusion detection algorithm that is analyzed using stroke duration measurements and/or long end stop duration pump measurements. These results are consistent with the following facts: leakage is primarily caused by wear and tear of the manifold seals after repeated pumping movements.

Table 2: occlusion detection with and without leak detection for subgroups of drug delivery devices 10 (10U bolus before clamping)

Thus, the leak detection criteria may be implemented in the occlusion detection algorithm. Since the algorithm only requires pump duration information to analyze the leak detection criteria, no hardware modifications are required. An occlusion detection algorithm employing leak detection criteria is improved when implemented in series with the stroke duration criteria and/or end stop switch activation duration criteria to more fully capture all important pump behavior during an occlusion.

It will be appreciated by persons skilled in the art that the present disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. Embodiments herein are capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including," "comprising," or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms "connected," "coupled," and "mounted," and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. In addition, the terms "connected" and "coupled" and variations thereof are not restricted to physical or mechanical connections or couplings. Further, terms such as upper, lower, bottom, and top are relative and are used to aid in explanation, but not limitation.

The components of the exemplary apparatus, systems, and methods employed in accordance with the illustrated embodiments of the present invention may be implemented, at least in part, in digital electronic circuitry, analog electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. For example, these components may be implemented as, for example, a computer program product, such as a computer program, program code, or computer instructions tangibly embodied in an information carrier or in a machine-readable storage device, for execution by, or to control the operation of, data processing apparatus (e.g., a programmable processor, a computer, or multiple computers).

A computer program can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network. Also, functional programs, codes, and code segments for implementing exemplary embodiments of the present invention may be easily construed as being within the scope of the present invention by programmers in the art to which the present invention pertains. Method steps associated with example embodiments of the present invention may be performed by one or more programmable processors executing a computer program, code, or instructions to perform functions (e.g., by operating on input data and/or generating output data). Method steps may also be performed by, and apparatus of exemplary embodiments of the present invention may be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit).

The various illustrative logical blocks, modules, and circuits described in connection with the embodiments disclosed herein may be implemented or performed with a general purpose processor, a Digital Signal Processor (DSP), an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto-optical disks, or optical disks. Information carriers suitable for embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, such as electrically programmable read-only memory or ROM (eprom), electrically erasable programmable ROM (eeprom), flash memory devices, and data storage disks (e.g., magnetic disks, internal hard disks, or removable disks, magneto-optical disks, and CD-ROM and DVD-ROM disks). The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

Those of skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure. A software module may reside in Random Access Memory (RAM), flash memory, ROM, EPROM, EEPROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. In other words, the processor and the storage medium may reside in an integrated circuit or be implemented as discrete components.

Computer-readable non-transitory media include all types of computer-readable media, including magnetic storage media, optical storage media, flash memory media, and solid state storage media. It should be understood that the software may be installed in and sold with a Central Processing Unit (CPU) device. Alternatively, the software may be obtained and loaded into the CPU device, including by obtaining the software through a physical medium or distribution system, including for example, from a server owned by the software creator or from a server not owned but used by the software creator. For example, the software may be stored on a server for distribution over the internet.

The description and drawings presented above are intended by way of example only and are not intended to limit the present invention in any way, except as set forth in the following claims. It is particularly noted that the various technical aspects of the various elements of the various exemplary embodiments that have been described above may be readily combined in a variety of other ways by those skilled in the art, all of which are considered to be within the scope of the present invention.

Claims (5)

1. An infusion device with integrated occlusion sensing, the infusion device comprising:

a pump, the pump comprising: a chamber configured with at least one port to receive fluid from a reservoir into the chamber and through which fluid flows out of the chamber; and a pumping mechanism configured to control aspiration of an amount of fluid into the chamber during an aspiration stroke and to control dispensing of an amount of fluid from the chamber during a dispensing stroke;

a pump measurement device configured to generate a pump measurement value related to at least one of each aspiration stroke performed by the pump and each dispense stroke performed by the pump; and

a processing device configured to analyze pump measurements and determine when a pump measurement comprises a plurality of pump measurements that satisfy a predetermined metric specified as an indication of occlusion, the pump measurement comprising a pump measurement for each of a plurality of strokes in at least one of the aspiration stroke and the dispense stroke;

wherein the pump measuring device is a switch configured to be activated by the pumping mechanism during operation.

2. The infusion device with integrated occlusion sensing of claim 1, further comprising an indicator operable as an occlusion alarm in response to the processing device determining that a plurality of pump measurements satisfy the predetermined metric.

3. The infusion device with integrated occlusion sensing of claim 1, wherein the switch is at least one of an end stop switch or a limit switch on the pump, the end stop switch configured to be activated upon completion of at least one of the aspiration stroke and the dispensing stroke by the pumping mechanism, the end stop switch connected to the processing device to determine a duration of each of the at least one of the aspiration stroke and the dispensing stroke.

4. The infusion device with integrated occlusion sensing of claim 1, wherein said switch is a switch selected from the group consisting of an electrical switch and an optical switch.

5. The infusion device with integrated occlusion sensing of claim 4, wherein the switch is an optical switch, the pump further comprising an encoder operable with the optical switch to determine a position of at least one component of the pumping mechanism during operation.

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